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                                                                   EXHIBIT 10.28

                THIRD AMENDMENT TO CREDIT AND SECURITY AGREEMENT

         This Amendment, dated as of November 13, 2003, is made by and between
METRETEK, INCORPORATED, a Florida corporation (the "Borrower"), and WELLS FARGO
BUSINESS CREDIT, INC., a Minnesota corporation (the "Lender").

                                    RECITALS

         The Borrower and the Lender are parties to a Credit and Security
Agreement dated as of September 6, 2002, as amended by (i) a First Amendment to
Credit and Security Agreement and Waiver of Defaults dated as of March 26, 2003
and (ii) a Second Amendment to Credit and Security Agreement dated as of
September 24, 2003 (as so amended, the "Credit Agreement"). Capitalized terms
used in these recitals have the meanings given to them in the Credit Agreement
unless otherwise specified.

         The Borrower has requested that certain amendments be made to the
Credit Agreement, which the Lender is willing to make pursuant to the terms and
conditions set forth herein.

         NOW, THEREFORE, in consideration of the premises and of the mutual
covenants and agreements herein contained, it is agreed as follows:

         1.       Defined Terms. Capitalized terms used in this Amendment which
are defined in the Credit Agreement shall have the same meanings as defined
therein, unless otherwise defined herein.

         2.       Section 6.2(c). Section 6.2(c) of the Credit Agreement is
amended and restated in its entirety to read as follows:

                  "(c)     CAPITAL EXPENDITURES. The Borrower will not incur or
contract to incur unfinanced Capital Expenditures of more than $750,000 in the
aggregate during the fiscal year ending December 31, 2003."

         3.       Exhibit B. Exhibit B of the Credit Agreement is amended and
restated in its entirety and replaced with Exhibit B attached hereto.

         4.       No Other Changes. Except as explicitly amended by this
Amendment, all of the terms and conditions of the Credit Agreement shall remain
in full force and effect and shall apply to any advance or letter of credit
thereunder.

         5.       Conditions Precedent. This Amendment shall be effective when
the Lender shall have received an executed original hereof, together with each
of the following, each in substance and form acceptable to the Lender in its
sole discretion:

                  (a)      The Acknowledgment and Agreement of Guarantors and
the Acknowledgment and Agreement of Subordinated Creditor set forth at the end
of this Amendment, duly executed by each Guarantor and Subordinated Creditor.

                  (b)      Such other matters as the Lender may require.

         6.       Representations and Warranties. The Borrower hereby represents
and warrants to the Lender as follows:

                  (a)      The Borrower has all requisite power and authority to
execute this Amendment and to perform all of its obligations hereunder, and this
Amendment has been duly executed and delivered by the Borrower and constitutes
the legal, valid and binding obligation of the Borrower, enforceable in
accordance with its terms.

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                  (b)      The execution, delivery and performance by the
Borrower of this Amendment has been duly authorized by all necessary corporate
action and does not (i) require any authorization, consent or approval by any
governmental department, commission, board, bureau, agency or instrumentality,
domestic or foreign, (ii) violate any provision of any law, rule or regulation
or of any order, writ, injunction or decree presently in effect, having
applicability to the Borrower, or the articles of incorporation or by-laws of
the Borrower, or (iii) result in a breach of or constitute a default under any
indenture or loan or credit agreement or any other agreement, lease or
instrument to which the Borrower is a party or by which it or its properties may
be bound or affected.

                  (c)      All of the representations and warranties contained
in Article V of the Credit Agreement are correct on and as of the date hereof as
though made on and as of such date, except to the extent that such
representations and warranties relate solely to an earlier date.

         7.       References. All references in the Credit Agreement to "this
Agreement" shall be deemed to refer to the Credit Agreement as amended hereby;
and any and all references in the Security Documents to the Credit Agreement
shall be deemed to refer to the Credit Agreement as amended hereby.

         8.       No Other Waiver. The execution of this Amendment and
acceptance of any documents related hereto shall not be deemed to be a waiver of
any Default or Event of Default under the Credit Agreement or breach, default or
event of default under any Security Document or other document held by the
Lender, whether or not known to the Lender and whether or not existing on the
date of this Amendment.

         9.       Release. The Borrower, and each Guarantor by signing the
Acknowledgment and Agreement of Guarantors set forth below, and the Subordinated
Creditor by signing the Acknowledgment and Agreement of Subordinated Creditor
set forth below, each hereby absolutely and unconditionally releases and forever
discharges the Lender, and any and all participants, parent corporations,
subsidiary corporations, affiliated corporations, insurers, indemnitors,
successors and assigns thereof, together with all of the present and former
directors, officers, agents and employees of any of the foregoing, from any and
all claims, demands or causes of action of any kind, nature or description,
whether arising in law or equity or upon contract or tort or under any state or
federal law or otherwise, which the Borrower or such Guarantor or such
Subordinated Creditor has had, now has or has made claim to have against any
such person for or by reason of any act, omission, matter, cause or thing
whatsoever arising from the beginning of time to and including the date of this
Amendment, whether such claims, demands and causes of action are matured or
unmatured or known or unknown.

         10.      Costs and Expenses. The Borrower hereby reaffirms its
agreement under the Credit Agreement to pay or reimburse the Lender on demand
for all costs and expenses incurred by the Lender in connection with the Loan
Documents, including without limitation all reasonable fees and disbursements of
legal counsel. Without limiting the generality of the foregoing, the Borrower
specifically agrees to pay all fees and disbursements of counsel to the Lender
for the services performed by such counsel in connection with the preparation of
this Amendment and the documents and instruments incidental hereto. The Borrower
hereby agrees that the Lender may, at any time or from time to time in its sole
discretion and without further authorization by the Borrower, make a loan to the
Borrower under the Credit Agreement, or apply the proceeds of any loan, for the
purpose of paying any such fees, disbursements, costs and expenses.

         11.      Miscellaneous. This Amendment and the Acknowledgment and
Agreement of Guarantors and the Acknowledgment and Agreement of Subordinated
Creditor may be executed in any number of counterparts, each of which when so
executed and delivered shall be deemed an original and all of which
counterparts, taken together, shall constitute one and the same instrument.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first written above.

WELLS FARGO BUSINESS CREDIT, INC.                METRETEK, INCORPORATED

By:    /s/ Patti Scudder                         By:   /s/ A. Bradley Gabbard
       -------------------------------------           ----------------------
Name:  Patti Scudder                             Name: A. Bradley Gabbard
Its:   Commercial Banking Officer                Its:  Chief Financial Officer

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